• by Erik Sass  @eriksass1, December 13, 2010

Arbitron can rest a little easier today, with the surprise announcement from Nielsen Co. that it is shutting down its nascent radio ratings service. The diary-based ratings, which used stickers in place of handwritten entries, had been available in 51 mid-sized radio markets, where they competed with Arbitron's long-established diary ratings. 

The statement from Nielsen reads: "The Nielsen Company has decided to end its measurement of radio in the United States, as of the Fall 2010 period. Back data and limited access to Radio Advisor software will continue to be available for use by Nielsen clients, as required." Neilsen began radio ratings in 2008.

These clients include Cumulus and Clear Channel Radio, which both supported the new Nielsen service as an alternative to Arbitron's de facto monopoly.

The decision does not impact Nielsen's international radio measurement, which serves 11 countries.

Nielsen's departure solidifies Arbitron's dominance in the marketplace -- a position that it has struggled to maintain over the last few years in the face of competition. It has also endured criticism from clients over the pricing and accuracy of both its diary service and ratings generated by the Portable People Meter, a passive electronic measurement device.

In the most public controversy, Arbitron faced off against minority broadcasters, which charged its sample methodology under-counted key minority audiences, including African-American and Hispanic men, leading to apparent declines in minority audience sizes.

The high-profile dispute, which led to civil-rights lawsuits and hearings by Congress and the Federal Communications Commission, was only resolved after a number of minority ad agencies and broadcasters joined the Media Rating Council and Arbitron promised to take steps to boost minority representation in its samples. In addition, most of Arbitron's top management was replaced.